Electrolytic cell



Nov. 20, 1934. v. ENGELHRDT ET AL EJECTROLYTIC CELL Filed Nov. 19, 1932 Iwedrs Viktori? eliza/rdb Nicolaus chn eldb .EM-S Wu Attorney Patented Nov. 20, 1 934 UNITED STATES 'PATENT OFFICE ELECTROLYTIC CELL Victor Engelhardt and Nikolaus Schnfeldt, Berlin Charlottenburg,

Germany, assignors to Siemens 85 Halske, Aktiengesellschaft, Semensstadt, near Berlin, Germany, a. corporation oi' Germany Application November 19, 1932, Serial No. &13,424 In Germany December 9, 1931 Clams.

ployed as a cathode and is electrically connected' with the mercury by high-ohmic resistances, for instance of graphite. Between the mercury and the anodes is usually located a porous partition wall, which preferably forms part of the walls of the tank or vat containing the mercury.

Our invention relates to a further improvement or development of such a cell, which enables a substantial saving of mercury to be efiected.

According to our invention the mercury of the i cell is contained in central longitudinal channels or bores provided in one or a plurality oi spaced extensions depending from a carrier member or horizontal partition wall. This carrier member forms the upper closure or cover of the anode compartment of the cell and also serves as a partition supporting a quantity of mercury which connects the columns of mercury contained in said recesses in the said bars; this mercury being in contact with the water fiowing around the cathode. The space between the anodes and the chambered porous bars is filled with the solution oi' alkaline metal halides to be electrolyzed. Preferably the horizontally disposed carrier member for the porous bars and the bars themselves, vertically Suspended therefrom, form a single unit. In an advantageous form the underside of the carrier member for the bars is provided with a cover impermeable to gas, more particularly with a protective coating,.to prevent the escape of the halogen gas, such as chlorine gas, developing at the anodes.

The single figure of the drawing afiixed to our specification and forming part thereof illustrates %ne embodiment of our invention invertical sec- Referring to the drawing, it will be observed that in the tank, bath or vat of ceramic material 5, for instance, there is located a non-porous horizontal partition wall 1, which at its underside carries substantially vertical porous bars 2 provided with elongated longitudinal channels 3 produced by boring, milling, moulding or in any other suitable manner. The bars consist preferably of an electrically non-conducting material,

such as,clay or earthenware. This also holds good fer the horizontal partition wall. A dotted line indicates up to what point the bars 2 should consist of porous material. Advantageously, however, the horizontal partition wall and the bars 2 are constructed of a porous material and the porosity of the horizontal partition wall is neutralized by a protective coating provided on its underside which fills up the pores. This protective coating prevents the chlorine gas from passing through the horizontal partition wall and entering the cathode compartment. Pipes 4 opening into the anode compartment serve for the discharge of the chlorine gas. The electrolysis apparatus or electrolyzer proper 5 contains the anodes 7 and the solution of the halides of the alkali or alkaline earth metals 6, as well as the leads from the source of current, not shown in the drawing, to the anodes.

The channels or bores 3 which are milled or bored in the longitudinal direction of the bars 2, the bore e'xtending to a point not quite to the ends of the bars, are filled with mercury 8 used -in such quantity that its level is above the horizontal partition wall and connects the mercury contained in the various channels. The cathode consists of wire netting 9 stretched across feet or supports 10 of graphite placed on the horizontal -partition wall so that the feet 10 dip into the mercury. Above the mercury, water 11 is introduced into the apparatus and serves for the decompcsition of the amalgam which forms. It will be understood that the constructional details of the apparatus may be changed in various ways and that already known details of other cells may be V applied to our improved cell.

We claim as our invention:

1. In a cell having anode and cathode compartments for the electrolytic decomposition of alkaline metal halides, a horizontal partition separating said anode and cathode 'compartments, a plurality of spaced channeled extensions of said partition depending into said anode compartment, said extensions being porous, adapted to hold mercury and the channels thereof being in communication with said cathode compartment, and a body of mercury in said cathode compartment covering said partition and exv tending into and filling said channels.

2. In a cell having anode and cathode compartments for the electrolytic decomposition of alkaline metal halides, a horizontal partition of porous material separatng said anode and cathode compartments, a plurality of spaced integral extensions of said porous material extending into said 4 anode compartment, the said extensions having ments for the electrolytic decomposition of alkoline metal halides, a. removable horizontal partition separating said anode and cathode Compartments, a plurality of spaced chambered extensions of said partition depending into said anode compartment, said extensions being porous, the said channeled extensions and the said parfition being adapted to hold a body of mercury, :modes in said anode compartment disposed between said channeled extensions and a body of mercury covering the top of said partition and extending into and filling said channeled extensions.

VICTOR ENGELHARDT. NIKOLAUS SCHNFELDT. 

